Everyone knows the best way to smuggle drugs is stashing that weight inside something that's not typically associated with illicitness, i.e hollowed-out copies of holy texts, extra-large coconuts, live Labrador retriever puppies, etc.
So stuffing your four-year-old niece's Hello Kitty backpack full of pills isn't a bad strategy for evading the authorities. Or at least it wasn't two decades ago when some anonymous genius first dreamed up the scheme.
Today, though, it's the equivalent of formally applying for a full cavity search. Sure, you might get lucky and come across lax law enforcement. But if you don't, you'll never be able to whisper "Hello World!" again without crying.
For females, it's Sanrio stuff. For dudes, it's Sesame Street.